ABSTRACT Under controlled, hatchery conditions, three experiments were conducted with embryos of Nassau grouper, Epinephelus striatus, to determine the effects of turbulence, salinity, and light intensity on hatching, growth (notochord length), and survival of yolksac larvae to the first-feeding stage (3 days post-hatch). Fertilized eggs were stocked (20 eggs/L) in tanks containing 500 L seawa-ter (36 g/L salinity) at 26°C and under an 11L:13D photoperiod. In Experiment 1, four levels of turbulence, produced by diffused aeration levels of 0.00, 0.15, 0.30, and 0.45 L/minute were compared. Hatching rates (mean = 80.3%) and growth were not significantly affected by turbulence level. Survival was negligible (0.17%) under static conditions and decreased (P< 0.05) with increasing turbulence from 39.5% at 0.15 L/minute to 13.2% at 0.45 L/minute, suggesting that low turbulence levels are optimal. In Experiment 2, four treatment salinities (24, 28, 32, and 36 g/L) were compared. Hatching rate was higher (P <0.05) at 32-36 g/L (64.9-76.3%) than at 24 g/L(46.4%). Growth did not differ among salinities, but survival was higher (P <0.05) at the higher salinities of 32-36 g/L (16.5-17.4%) than at salinities of 24-28 g/L (0.475-3.94%). In Experiment 3, three light intensities-1,636 lux (high), 714 lux (low), and 0 lux (dark-ness)-were compared under an aeration rate of 0.15 L/minute and salinity of 38 g/L. Hatching rates (mean = 67.3%) were not significantly different (P >0.05). Mean notochord length was higher (P <0.05) for larvae exposed to low light (2.95 mm) or darkness (2.94 mm) than for those exposed to high light intensity (2.86 mm). Survival increased (P < 0.05) with light intensity from 18.7% in darkness to 36.3% at 1,636 lux. Based on survival values, a minimum turbulence level for larval dispersion, salinities of 32-36 g/L, and a light intensity of approximately 1,636 lux is recommended for culture of Nassau grouper to the first-feeding stage.